modalities for management of tumor in head and neck region

1. Department of Oral and Maxillofacial Surgery, CODS, BPKIHS
Management of Jaw Tumors
Presented by
Ujwal Gautam
Roll no 431
BDS 2009

2. Contents
• Diagnosis
• Treatment Planning
• Principles of Surgical excision
• Radiotherapy: indications
• Reconstruction
• Complications
• Survival and Prognosis

3. Diagnosis
 History and Examination
 Biopsy
 Imaging

4. History & Examination
History of the lesion
Duration
Mode of onset and progress
Exact site and shape
Change in character of the lesion
Associate symptoms
Similar swelling elsewhere
Loss of body weight
Recurrence
Habit

5. History & Examination
Inspection
Number
Size
Site or anatomical location
Shape and size
Colour
Surface
Pedunculated/sessile
Overlying skin
Clinical Examination of the Lesion
Palpation
Consistency of lesion
Presence of pulsation
Fixity
Lymph node examination

6. History & Examination
 Bleeding
 Duration >2 wks
 Erythroplasia
 Fixidity
 Rapid growth
 Induration
 Ulceration
Characteristics of malignant Lesion:

7. Biopsy
Indications;
• Any persistent pathologic condition that cannot be clinically diagnosed
• Lesions with no identifiable cause that persists for greater than 2 weeks despite
local therapy
• Enlarging intrabony lesions
• Visible/ palpable submucosal swelling beneath clinically normal mucosa
• Any lesion with malignant/ premalignant characteristics
• Confirmation of clinical diagnosis
• Lesions not responding to routine clinical management over 2 weeks
• Any lesion that is of extreme concern for patient

8. Biopsy
• Cytologic techniques
• Incisional biopsy
• Excisional biopsy
• Aspiration biopsy

9. Incision Biopsy
Indications:
 Large lesion > 1 cm diameter
 Location in risky or hazardous
regions
Principles
 Site is carefully chosen after thorough clinical and radiological
examination
 Aspiration is always tried before
 Incision in wedge shaped fashion
 Normal tissue should be included
 Tissue specimen should not be crushed
 Deeper biopsies over superficial ones
 Proper hemostasis before closure
 Specimen should be well oriented and marked
 Tissue is immediately placed in formalin

12. Intraosseous Biopsy
ı Performed after thorough Neck examination as cervical lymphadenitis is
inevitable after the procedure rendering clinical neck examination to produce
false positive results
ı Necessary because diagnosis from frozen section not possible
ı Site: Extraction socket or flap reflection
ı Full thickness mucoperiosteal flap of adequate extention is made.
ı Flap should rest entirely on sound bone for closure. Eroded area of cortical
bone should be approached from the lesion margins over sound bone.
ı Major neurovascular structures should be avoided.
ı Precautionary aspiration performed before biopsy to prevent inadverant
excision into vascular lesion.
ı Osseous window created on the cortical plate either with bur of rongeurs.
ı Specimen can be curetted from the surrounding bone.

13. Imaging
 OPG
 CT
 MRI
 PET

14. Tumors of odontogenic
epithelium
o Ameloblastoma
• Malignant ameloblastoma
• Ameloblastic carcinoma
o Calcifying epithelial
odontogenic tumor
o Squamous odontogenic tumor
o Clear cell odontogenic
carcinoma
o Primary intraosseous carcinoma
Tumors of odontogenic epithelium
With odontogenic ectomesenchyme
± dental hard tissue formation
o Ameloblastic fibroma
o Ameloblastic fibro-odontoma
o Ameloblastic fibrosarcoma
o Odontoameloblastoma
o Odontoma
• Compound composite
• Complex composite
o Adenomatoid odontogenic tumor
Tumors of odontogenic
ectomesenchyme
± included odontogenic
epithelium
o Odontogenic fibroma
o Granular cell odontogenic
tumor
o Odontogenic myxoma
o Cementoblastoma
Benign Odontogenic tumors

15. Benign Non-odontogenic tumors
Osteogenic neoplasm
o Ossifying fibroma
o Osteoma
Non neoplastic bone lesions
o Fibrous Dysplasia
o Cementoosseous dysplasia
• Periapical
cementoosseous dysplasia
• Focal cementoosseous
dysplasia
• Florid cementoosseous
dysplasia
Other cementoosseous dysplasia
o Cherubism
o Central Giant Cell Granuloma

16. Odontogenic Carcinomas
o Malignant (metastasizing) ameloblastoma
o Ameloblastic carcinoma
• Primary
• Dedifferentiated
• Peripheral
o Primary intraosseous squamous cell carcinoma
• Solid
• Cystogenic
 Nonkeratinizing cyst
 Odontogenic keratocyst
o Clear cell odontogenic carcinoma
o Malignant epithelial odontogenic ghost cell
tumor
Odontogenic Sarcoma
o Ameloblastic fibrosarcoma
Odontogenic malignancies

17. Non Odontogenic malignancies
o Osteosarcoma
o Fibrosarcoma and chondrosarcoma
o Squamous cell carcinoma
o Secondary (metastatic) bone tumours

18. Peak age Adults, about 40 years old.
Frequency Rare, but still the most common odontogenic tumour; 1% of all oral
tumors, 18% of all odontogenic tumors
Site Posterior body/angle/ramus of mandible, very occasionally involves the
maxilla.
Clinical Feature asymptomatic, slow growing, hard, non tender, ovoid
swelling; may be associated with mobile teeth, exfoliation of teeth, ill fitting
dentures, malocclusion, paraesthesia or ulcerations; large lesion may present
with egg shell crackling
Ameloblastoma

19. Shape
— Multilocular, distinct septa dividing the lesion into compartments with large,
apparently discrete areas centrally and with smaller areas on the periphery;
Occasionally monolocular in early stages
— Honeycomb or soap-bubble appearance or multicystic
— shape varies with different histological subtypes.
Outline
— Smooth and scalloped; Well defined, Well corticated.
Radiodensity Radiolucent with internal radiopaque septa.
Effects
— Adjacent teeth displaced, loosened, often resorbed
— Extensive expansion in all dimensions; Buccolongual cortical expansion prominent
Thin “eggshell” cortical bone
— Maxillary lesions can extend into the paranasal sinuses, orbit or base of the skull

21. Odontomes
Age 1st and 2nd decades
Site commonly seen in; posterior mandible, anterior maxilla esp in third
molar region
Clinical Features asymptomatic, no obvious bony or facial asymmetry; may
be associated with unerupted teeth

22. Compound odontome
It is made up of several small toothlike
denticles. The miniature tooth shapes are
of dental tissue radiodensity, with a
surrounding radiolucent line, and are
easily identified radiographically.
Complex odontome
This odontome is made up of an irregular,
confused mass of dental tissues bearing
no resemblance in shape to a tooth. The
enamel content provides the dense
radiopacity, suggestive of dental tissue
and again the mass is surrounded by a
radiolucent line

23. Fibrous dysplasia
Age 10-20 year-old adolescents.
Site Maxilla — usually posteriorly, more commonly than the mandible.
Maxillary lesions may spread to involve adjacent bones such as the zygoma,
sphenoid, occiput and base of skull.
Size Variable and difficult to define.
Shape Round.

24. Outline
— Poorly defined with the margins merging imperceptibly with adjacent normal bone
— Not corticated.
Radiodensity
— Initially radiolucent (but rarely seen clinically at this stage)
— Gradually becomes opaque to produce the typical ground glass, orange peel and
finger print appearances resulting from superimposition of many fine, poorly-calcified
bone trabeculae arranged in a disorganized fashion.
— Continuing to become more opaque with age.
Effects
— Adjacent teeth
— sometimes displaced but rarely resorbed
— loss of associated lamina dura
— Buccal and lingual alveolar expansion
— Encroachment on, or obliteration of, the antrum
— Involvement of adjacent bones including the base of the skull.

26. Age Younger adults lesser than 30 years old.
Frequency Rare, but the most common primary malignant bone tumour.
Site Usually the mandible.
Size
Shape
Outline
Radiodensity
From a radiological viewpoint, there are three main types:
Osteolytic — no neoplastic bone formation
Osteosclerotic — neoplastic osteoid and bone formed
Mixed lytic and sclerotic — patches of neoplastic bone formed.
All very variable
depending on the type of
lesion (lytic or sclerotic)
and how long it has been
present.
Osteosarcoma

27. Effects
Early features: Non-specific, poorly defined radiolucent area around one or more
teeth. Widening of the periodontal ligament space.
Later features:
• Osteolytic lesion:
— Monolocular, ragged area of radiolucency
— Poorly defined, moth-eaten outline.
— Cumulous cloud densities
— So-called spiking resorption and/or loosening of associated teeth.
• Osteosclerotic and mixed lesions:
— Poorly defined radiolucent area
— Variable internal radiopacity with obliteration of the normal trabecular
pattern
— Perforation and expansion of the cortical margins by stretching the
periosteum, producing the classical, but rare sun ray or sunburst appearance
— Spiking resorption and/or loosening of associated teeth
— Distortion of the alveolar ridge

29. Squamous cell carcinomas of the oral mucosadirectly overlying bone, in their latter
stages, often invade the underlying bone to produce a destructive radiolucency.
Age Adults over 50 years old.
Frequency Rare, but the most common oral malignant tumour.
Site Mandible, or maxilla if originating in the antrum.
Size Variable.
Squamous cell carcinoma

30. Shape Irregular area of bone destruction often initially saucer-shaped.
Outline
— Irregular and moth-eaten
— Poorly defined
— Not corticated.
Radiodensity Radiolucent, radiodensity dependent on degree of destruction.
Effects
— Adjacent teeth may be displaced, loosened and/or resorbed or left
floating in space
— Destruction of surrounding bone may lead to pathological fracture.

33. Treatment Planning
 Diagnosis confirmed by biopsy
 Imaging for assessment of extension
 For malignant lesions;
• Evaluation for staging; Neck assessment
• Approach for primaries: surgery/chemotherapy/radiotherapy
• Approach for secondaries
• Palliative approach
 For benign lesions;
• Surgical approach
 Reconstruction

34. General principles
Factors influencing treatment planning;
 Site of disease
 Stage
 Histology
 Age
 Previous radiotherapy
 Field change

36. Primary Tumors (T)
TX Primary tumor cannot be assessed
T0 No evidence of primary tumor
Tis Carcinoma in situ
T1 Tumor <=2 cm in greatest dimension
T2 Tumor >2 cm but <=4 cm in greatest dimension
T3 Tumor >4 cm in greatest dimension
T4a Tumor invades adjacent structures (eg, through
cortical bone, into deep
[extrinsic] muscle of the tongue, maxillary sinus, skin
of face) (resectable)
T4b Tumor invades masticator space, pterygoid
plates, or skull base or encases
internal carotid artery (unresectable)
Nodal Involvement (N)
NX Regional lymph nodes cannot be assessed
N0 No regional lymph node metastasis
N1 Metastasis in a single ipsilateral lymph node, <=3 cm in
greatest dimension
N2 Metastasis in a single ipsilateral lymph node, >3 cm but
<=6 cm in greatest dimension; or in multiple ipsilateral lymph
nodes,
<=6 cm in greatest dimension; or in bilateral or contralateral
lymph nodes, <=6 cm in greatest dimension
N2a Metastasis in a single ipsilateral lymph node >3 cm but
<=6 cm in greatest dimension
N2b Metastasis in multiple ipsilateral lymph nodes, <=6 cm in
greatest dimension
N2c Metastasis in bilateral or contralateral lymph nodes, <=6
cm
in greatest dimension
N3 Metastasis in a lymph node >6 cm in greatest dimension

37. Early
Stage
Locally
advanced,
operable
Locally
advanced,
inoperable/
metastatic
0
4
4

38. Principles of Surgical excision
of jaw tumors

39. Factors deciding Surgical modality
Aggressiveness of Lesions
Depends on biologic behavior of lesion depicted by histologic diagnosis.
Most Benign lesions treated conservatively without much destruction of
adjacent structures.

40. Factors deciding Surgical modality
Anatomic Location of Lesion
Lesion in easily accessible and resectable areas offer better
prognosis.

41. Factors deciding Surgical modality
Anatomic Location of Lesion
Maxilla vs mandible
Tumors in mandible are confined largely due to the thick cortical
plates but maxillary tumors tend to enlarge into the sinuses, orbit,
skull base and nasopharynx. They present a poorer prognosis.

42. Factors deciding Surgical modality
Anatomic Location of Lesion
Proximity to Adjacent Vital Structures
Benign lesions may cause damage to neurovascular structures and
teeth. Neurologic deficit and vascular compromise might occur.
Tumors can also be associated with root resorption.

43. Factors deciding Surgical modality
Anatomic Location of Lesion
Size of tumor
Larger tumor requires a larger segment of bone resection. Continuity
of mandible can be compromised leading to a more difficult
reconstruction process.

44. Factors deciding Surgical modality
Anatomic Location of Lesion
Intraosseous vs Extraosseous location
An aggressive oral lesion confined to the interior of jaw provides
better prognosis than a lesion invading surrounding soft tissues.

45. Factors deciding Surgical modality
Duration of Lesion
Slow growing lesions follow a benign course and hence treated
accordingly.

46. Factors deciding Surgical modality
Reconstructive efforts
Reconstructive procedures should be planned and anticipated
before surgery.

47. Modalities of Surgical excision
 Enucleation (with or without curettage)
 Resection
 Marginal Resection
 Partial Resection
 Total Resection
 Composite Resection

48. Modalities of Surgical excision
 Enucleation (with or without curettage)
Indications:
• Tumors with expansile growth rather than by infiltration
• Well defined lesion with distinct separation from surrounding
tissue
• Tumor with corticated lining

49. Modalities of Surgical excision
 Marginal/En bloc Resection
(Resection without continuity defect)
Indications:
• Recurrent lesion previously treated by enucleation alone
• Incompletely encapsulated or tendency to grow beyond
surgically apparent capsule

50. Modalities of Surgical excision
 Marginal/En bloc Resection
(Resection without continuity defect)
Indications(for malignancy):
• Horizontal mandibulectomy for Gingivobuccal cancer reaching
close to mandible but not grossly involving mandible
• Lingual plate excision for lesions of floor of mouth or tongue
• Buccal plate excision for lesions of gingivobuccal complex with
minimal paramandibular spread
• Minimal cortical erosion

51. Modalities of Surgical excision
 Segmental Resection
(Resection with continuity defect)
Indications:
• Lesions with infiltrative tendency
• Extension closer to inferior or posterior border of mandible,
maxillary sinus or nasal cavity
• High recurrence
• Lesions with chances of post operative fracture

52. Modalities of Surgical excision
Segmental Resection of Mandible:
– Hemimandibulectomy
– segmental mandibulectomy
– posterior segmental
– middle segmental
– Disarticulation

53. Modalities of Surgical excision
Disarticulation
Whenever condylar head is included in the resection part of the
mandible, the procedure is known as hemi-mandibulectomy with
disarticulation and whereas the condylar head is retained for
rehabilitation procedure, then the procedure is known as hemi-
mandibulectomy without disarticulation

54. Modalities of Surgical excision
 Total Resection
Resection of tumor with removal of involved bone
Involves:
Mandibulectomy
Maxillectomy

55. Modalities of Surgical excision
Maxillectomy
 Total: it refers to surgical resection of the entire maxilla.
Resection includes the floor and medial wall of the orbit and
the ethmoid sinuses.
 Sub total inferior: on alveolar ridge, palate, antral floor
 Sub total anterior: for lesions anterior to maxillary 1st
premolar

56. Modalities of Surgical excision
Modifications for Total Maxillectomy
1. When the tumor extends up to the roof of the maxillary sinus
(but does not invade) the orbital floor should be included in
the resection
2. When the tumor invades the roof of the maxillary sinus, the
orbit or the ethmoidal sinuses, orbital exenteration is
mandatory
3. Tumors confined to the posterior aspect of the maxillary sinus
is managed with conservative resection sparing maxilla

58. Modalities of Surgical excision
 Composite Resection
Most common ablative procedure for locally advanced
malignant lesions
Involves,
• removal of involved mucosa, skin, mandible with a margin of at
least 2-2.5 cm
• Removal of neck nodes

59. Modalities of Surgical excision
 Composite Resection
Neck dissection;
1. Radical Neck dissection
2. Modified Radical Neck dissection
3. Selective neck dissection
4. Extensive radical neck dissection

60. Radical Neck Dissection
removal of all ipsilateral cervical
lymph node groups extending from
the inferior border of the mandible to
the clavicle, from the lateral border of
the sternohyoid muscle, hyoid bone,
and contralateral anterior belly of the
digastric muscle medially, to the anterior
border of the trapezius. Included
are levels I through V. This entails the
removal of three important nonlymphatic
structures—the internal jugular
vein, the sternocleidomastoid muscle,
and the spinal accessory nerve.

61. Modified Radical Neck Dissection
removal of the same lymph
node levels (I through V) as the radical
neck dissection, but with preservation
of the spinal accessory nerve, the
internal jugular vein, or the sternocleidomastoid
muscle.

62. Selective Neck Dissection
preservation of one or more lymph
node groups normally removed in a
radical neck dissection.
Extended Neck Dissection
removal of one or more additional
lymph node groups, nonlymphatic
structures, or both, not encompassed
by a radical neck dissection

63. Enucleation Marginal or Partial resection Composite resection
Odontogenic tumors
Odontoma Ameloblastoma Malignant ameloblastoma
Ameloblastic fibroma Calcifying epithelial odontogenic tumor Ameloblastic fibrosarcoma
Ameloblastic fibroodontoma Myxoma Ameloblastic odontosarcoma
Adenomatoid odonogenic tumor Ameloblastic odontoma Primary intraosseous carcinoma
Calcifying odontogenic cyst Squamous odontogenic tumor
cementoblastoma
Central cementifying fibroma
Fibroosseous lesions
Central ossifying fibroma Benign chondroblastoma Fibrosarcoma
Fibrous dysplasia, Cherubism Osteosarcoma
Central giant cell granuloma Ewing’s sarcoma
Aneurysmal bone cyst Chondrosarcoma
Osteoma
Osteoid osteoma
osteoblastoma
Other lesions
Hemangioma hemangioma Lymphoma
Eosinophilic granuloma Carcinoma, adeno carcinoma, melanoma
Neurilemmoma, Neurofibroma neurofibrosarcoma

64. Criteria for inoperability
 Fixed neck nodal adenopathy
 Recent onset of trismus (gross infratemporal fossa invasion)
 Base skull involvement
 Extensive soft tissue involvement
 Distant metastasis

65. Radiotherapy
 Indications
 Multiple positive lymph nodes in the neck confirmatory of
metastasis
 Extracapsular extension by metastatic disease
 Perivascular or Perineural invasion
 Gross residual disease following surgery; positive surgical
resection margins
 Cranial nerve involvement or extension to skull base

66. Preradiotherapy
• Avoid radiation therapy for tumours involving the mandible
• Extract poor-prognosis teeth prior to starting treatment
• Remove cysts and odontomes
Postradiotherapy
• Stress on maintenance of oral and dental hygiene through and after radiation
therapy
• Avoid dental extraction, especially of multiple teeth after radiation therapy
• Removal of caries and extirpation of pulps
• Root canal therapy
• Prevent tooth loss
• Fluoride gel and mouthwashes
• Chlorhexidine mouthwashes
• Limit radiation caries with dental splint coverage
Considerations for patients undergoing
radiotherapy

67. Chemotherapy
Radiotherapy plus Cetuximab for Squamous-Cell Carcinoma of the Head and Neck
James A. Bonner, M.D., Paul M. Harari, M.D., Jordi Giralt, M.D., Nozar Azarnia, Ph.D., Dong M. Shin, M.D., Roger B. Cohen, M.D., Christopher U. Jones, M.D., Ranjan Sur,
M.D., Ph.D., David Raben, M.D., Jacek Jassem, M.D., Ph.D., Roger Ove, M.D., Ph.D., Merrill S. Kies, M.D., Jose Baselga, M.D., Hagop Youssoufian, M.D., Nadia Amellal, M.D.,
Eric K. Rowinsky, M.D., and K. Kian Ang, M.D., Ph.D.N Engl J Med 2006; 354:567-578February 9, 2006DOI: 10.1056/NEJMoa053422
BACKGROUND We conducted a multinational, randomized study to compare radiotherapy alone with radiotherapy plus cetuximab, a monoclonal antibody
against the epidermal growth factor receptor, in the treatment of locoregionally advanced squamous-cell carcinoma of the head and neck
METHODS Patients with locoregionally advanced head and neck cancer were randomly assigned to treatment with high-dose radiotherapy
alone (213 patients) or high-dose radiotherapy plus weekly cetuximab (211 patients) at an initial dose of 400 mg per square meter of body-
surface area, followed by 250 mg per square meter weekly for the duration of radiotherapy. The primary end point was the duration of control
of locoregional disease; secondary end points were overall survival, progression-free survival, the response rate, and safety.
RESULTS The median duration of locoregional control was 24.4 months among patients treated with cetuximab plus radiotherapy and 14.9 months among
those given radiotherapy alone (hazard ratio for locoregional progression or death, 0.68; P=0.005). With a median follow-up of 54.0 months, the median
duration of overall survival was 49.0 months among patients treated with combined therapy and 29.3 months among those treated with radiotherapy alone
(hazard ratio for death, 0.74; P=0.03). Radiotherapy plus cetuximab significantly prolonged progression-free survival (hazard ratio for disease progression
or death, 0.70; P=0.006). With the exception of acneiform rash and infusion reactions, the incidence of grade 3 or greater toxic effects, including mucositis,
did not differ significantly between the two groups.
CONCLUSIONS Treatment of locoregionally advanced head and neck cancer with concomitant high-dose radiotherapy plus cetuximab improves
locoregional control and reduces mortality without increasing the common toxic effects associated with radiotherapy to the head and neck

68. Reconstruction
 Objectives
 Achieve primary healing
 Maintain oral competence
 Facilitate swallowing
 Prevent aspiration
 Preserve speech
 Restore continuity, bone height and bone bulk of jaw

69. Immediate reconstruction
Advatages
o Single stage surgery
o Early return of function
o Minimal compromise of esthetics
Disadvantages
o Recurrence in grafted bone
o Loss of graft from infection
Techniques:
1. Performing surgical excision and grafting, both
via intraoral approach
2. Surgical excision utilizing both intraoral and
extraoral approach; first obtaining water tight
oral closure and grafting done extraorally
3. Earlier extraction of involved teeth and waiting
for 6-8 wks for oral healing and surgery via
extraoral approach later
Reconstruction of Osseous Defect

70. Delayed reconstruction
• usually performed after 6 months of waiting period to observe for
recurrence
• Preferred in malignancies
• If rediotheray is anticiopated as it may jeopardise the graft
• Residual mandibular fragments are maintained with their normal
anatomic relationship (IMF/ Reconstruction plate) in order to avoid
muscular deformation and displacement of segments
Reconstruction of Osseous Defect

71. Modalities for repair of defect
 Primary closure
 Split thickness graft
 Pedicled flap
 Free composite graft with microvascular reconstruction

72. Modalities for repair of defect
Flap: bailey

73. Modalities for repair of defect

74. Modalities for repair of defect
Anatomical site Microvascular free flap Alternative flaps
Floor of mouth Forearm Nasolabial flap(b/l)
Lateral tongue Forearm Platysma skin flap
Total tongue/glossectomy Rectus abdominus Pectoralis major
Buccal mucosa Forearm Temporalis muscle
Mandible
Dentate Iliac crest Fibula
Edentate Fibula Reconstruction plate, pectoralis
Maxilla
Low level/hard palate Temporalis muscle Forearm
High Iliac crest Fibula
Soft palate/tonsil Forearm Temporalis, pectoralis muscle
Tongue base forearm Pectoralis major

75. Complications
 Surgery
 Accessory nerve palsy: shoulder dysfunction and pain
 Soft tissue oedema
 Phrenic nerve injury
 Thoracic duct injury
 Cranial nerve injury
 Rupture of carotid artery

76. Complications
 Radiotherapy
 Osteoradionecrosis of mandible
 Hypothyroidism
 Atherosclerosis of carotid artery
 Neck and Shoulder dysfunction
 Trismus
 Xerostomia
 Dental caries
 Visual Impairment
 Radiation neuritis

77. Complications
 Chemotherapy
 Nausea and Vomiting
 Diarrhoea
 Stomatitis
 Gastrointestinal upset
 Renal Toxicity
 Leukopenia and thrombocytopenia

78. Survival & Prognosis
Prognostic factors
 Advanced stage has poor survival rate
 Carcinoma has poor prognosis than benign lesions
 Depends on site of lesion. Eg Lesions in posterior 1/3 of tongue has worst
prognosis
 Perineural invasion and angioinvasion has poor prognosis
 Tumor thickness >6 mm has poor prognosis
 Histologically positive lymph nodes carry poor prognosis

79. Survival & Prognosis
Stage of presentation
(for malignant lesions)
5 year Survival rate %
I 80 – 90
II 65 – 75
III 40 – 50
IV 30

80. References
Hupp, Ellis III, Tucker; Contemporary Oral and Maxillofacial Surgery; 5/e; Elsevier
Inc; 2008
Laskin DM; Oral and Maxillofacial surgery Vol. 2; Mosby Co.;1996
Malik NA; Textbook of Oral and Maxillofacial Surgery; 2/ed; Jaypee; 2008
Fonseca RJ; Oral and Maxillofacial Surgery Vol. 5; WB Saunders; 2000
Booth PW, Schendel SA, Hausamen JE; Maxillofacial Surgery Vol. 2; Harcourt Brace
and Co., 1999